Lifting-jack



2 Sheets-Shet 1.

(No Model.)

TISCHER.

LIFTING JACK.

Patented Nov. 4, 1890.

INVENTOR= 1 7J1 ede77i/7amisc7w/e 7 BY $6 ATT'Y.

M WITNgSgE;

(No Model.) 2 Sheets-Sheet 2.

F. TISOHER.

LIFTING JACK. No. 439,735. Patented Nov. 4, 1890.

10 WITNESSES: INVENTOR I fined/61 1370 Eli-307L617 UNITED STATES PATENT OFFICE.

FREDERICK TISOHER, OF NEWARK, NEW JERSEY.

LIFTlNG-JACK.

SPECIFICATION forming part of Letters Patent No. 439,735, dated November 4, 1890.

Application illel August 8,1890. Serial No. 361,432. (No model.)

To all whom it may concern.-

Be it known that I, FREDERICK TISCHER, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Lifting-Jacks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which appertains to make and use the same, reference 'joeing had to the accompanying drawings and to letters of reference marked thereon, which form a part of this specification.

The herein-described invention relates to improvements in a gear-screw lifting-jack; and it consists in the peculiar construction and combination of parts, as will be hereinafter more fully described, and finally embodied in the several clauses of the claim.

The invention is illustrated in the two sheets of drawings herewith accompanying, in which similar letters of reference are employed to indicate corresponding parts in each of the several views.

In said drawings, Figure l is a front elevation of my improved lifting-jack. Fig. 2 is a side elevationof the same; and Fig. 3 is a View similar to that shown in Fig. 1, andillustrating the construction of the opposite side of the jack. Fig. 4 is a top View of the same, and Fig. 5 is a horizontal section taken on line w in Fig. 2. On Sheet 2, Fig. 6 is a vertical section of the lifting-jack; and Fig. 7 is a view similar to that shown in Fig. 1, but with the gear-protecting plate removed. Fig. 8 is a plan view of the turn-table employed in the present construction, and Fig. 9 is a section taken on line y in said Fig. 8. Fig. 10 is a view similar to that shown in Fig. 8, with the top plate removed, illustrating the arrangement of rollers upon which certain parts of the jack rotate.

In said drawings, a indicates the base, which is provided, preferably near the upper part thereof, with an annular shoulder a, and around the upper part of said base is arranged the sleeve a resting upon said shoulder a and adapted to rotate thereupon.

From Fig. 6 it will be seen that the base a is tubular, being provided on the back thereof with an upwardly-projecting opening a and the sleeve a as clearly illustrated in Fig. 6.

The upper side of said disk 0' is inclined upwardly, as shown more especially in Fig. 9, and upon the same is placed a plate 0 provided with openings, or pockets 0 in which are arranged small steel rollers 0 which are tapered, as shown. The opposite sides of the disk 0 are inclined toward each other and toward the center of said disk, and the rollers are in the form of a truncated cone. Upon these rollers is arranged another plate 0 which is similar in cross-section to the plate 0'. The turn-table is provided with a centrally-arranged perforation c for arranging the same around the screw b. As willbe seen from Figs. 1, 2, 3, and 6, the upper end of the sleeve 6&2 is cup-shaped at a and within the same I have arranged a female screw or nut d, provided with teeth d on its under side. The male screw works through a threaded perforation d in said nut.

From Figs. 6 and 7 it will be seen that I have provided the sleeve a with a chambered portion, in which is arranged a gear e, mesh ing with said teeth 01' on the nut d, and also a gear 6, meshing with the smaller pinion e as shown. Said gears are provided with proper axles working in bearings a and a in the sleeve a and also in bearings in the protecting shield or plate f, secured over said chambered portion by means of screws f Said shield is provided with an upwardly-pro jecting lip f which covers the greater part of one side of the nut d. From this construction it will be evident that the gear mechanism is entirely protected, and no dirt or stones can fall between the teeth of the gear, and thus render the jack useless. The axles of the gears project out beyond the plate 1 and are squared to receive a crank or handle. The

crank can be placed on either end of the axles, raising the screw and its head much faster when applied to the large gear-wheel e, as will be evident, but receiving greater power when applied to the other gear.

Another great advantage is obtained by making the sleeve a with the upwardly-projecting and cup-shaped shoulder a, whereby the teeth d are entirely within the machine and cannot come in contact with the load resting upon the step I). A set-screw a extending into an annular groove a in the top part of the base, holds the sleeve in position thereon, still allowing the latter to turn on the shoulder a. If desirable, another set-screw a can be arranged on one side of the sleeve, as in Figs. 1 and 2, which can be tightened up against the side of the base a, whereby the sleeve is rigidly held and prevented from turning on the shoulder a.

Having thus described my invention, what I claim is 1. In a lifting-jack, the combination of a hollow base, a lifting-screw provided with a step, a turn-table on the upper part of said base, a cup-shaped sleeve arranged on a shoulder on said base, provided with one or more set-screws, a nut working on said screw and provided with teeth which are entirely protected by said cup-shaped sleeve, gear mechanism for operating said nut, and a protecting-plate)", provided with a lip f projecting over and above the nut on the liftingscrew, as and for the purposes set forth.

2. In a lifting-jack, the combination of a hollow base, a lifting-screw, a turn-table upon the upper part of said base, a sleeve a', surrounding the base and provided with one or more set-screws, as set forth, and means for raising and lowering said lifting-screw, as and for the purposes set forth.

3. In a 1ifti11g-, 'ack,the combination of a hollow base, a lifting-screw, a turn-table upon the upper part of said base, a sleeve a sur rounding the base and provided with one or more set-screws, as set forth, a nut on said screw provided with teeth on its under side, a gear 0, meshing therewith, gears e and c and a plate f, all of said parts being arranged as and for the purposes set forth.

4. In a lifti11g-jack,tl1e combination of a hollow base, a lifting-screw, a turn-table on the upper end of said base, consisting, essentially, of two disks 0 and c, as set forth, and a disk or plate arranged therebetween and provided with openings or pockets and tapered rollers therein, a sleeve a surrounding the base, extending above the same, and forming a chamber for said turn-table,whercby the same is entirely protected, one or more set-screws in said sleeve, as set forth, and means for raising and lowering said liftingscrew, as and for the purposes set forth.

In testimony that I claim the invention set forth above I have hereunto set my hand this 6th day of August, 1890.

FREDERICK TISOIIER.

Witnesses:

FREDERICK G. FRAENTZEL, WM. II. CAMFIELD. 

